/in/foo.cc:8:16: error: 'b' has not been declared
 int maxx(int a,b,c,d){
                ^
/in/foo.cc:8:18: error: 'c' has not been declared
 int maxx(int a,b,c,d){
                  ^
/in/foo.cc:8:20: error: 'd' has not been declared
 int maxx(int a,b,c,d){
                    ^
/in/foo.cc: In function 'int maxx(int, int, int, int)':
/in/foo.cc:9:6: error: 'b' was not declared in this scope
  if (b>a){
      ^
/in/foo.cc:12:5: error: 'c' was not declared in this scope
  if(c>a){
     ^
/in/foo.cc:15:5: error: 'd' was not declared in this scope
  if(d>a){
     ^